Published March 27, 2023
| Version v1
Publication
Velocity space resolved absolute measurement of fast ion losses induced by a tearing mode in the ASDEX Upgrade tokamak
Description
Absolute flux of fast ion losses induced by tearing modes have been measured by means
of fast ion loss detectors (FILD) for the first time in RF heated plasmas in the ASDEX
Upgrade tokamak. Up to 30 MW m−2
of fast ion losses are measured by FILD at 5 cm from
the separatrix, consistent with infra-red camera measurements, with energies in the range of
250–500 keV and pitch angles corresponding to large trapped orbits. A resonant interaction
between the fast ions in the high energy tail of the ICRF distribution and a m/n = 5/4 tearing
mode leads to enhanced fast ion losses. Around 9.3 ± 0.7% of the fast ion losses are found
to be coherent with the mode and scale linearly with its amplitude, indicating the convective
nature of the transport mechanism. Simulations have been carried out to estimate the
contribution of the prompt losses. A good agreement is found between the simulated and the
measured velocity space of the losses. The velocity space resonances that may be responsible
for the enhanced fast ion losses are identified.
Abstract
EUROfusion Consortium de la Unión Europea-Euratom 2014-2018/633053Abstract
Ministerio de Economía y Competitividad de España-RYC-2011-09152, FIS2015-69362-P y ENE2012-31087Additional details
Identifiers
- URL
- https://idus.us.es/handle//11441/143576
- URN
- urn:oai:idus.us.es:11441/143576